Force multiplying retaining straps

ABSTRACT

A generally U-sectioned cam buckle frame is modified to include a first turning roller aligned transversely across the frame proximate the free end of a release lever. A generally planar tongue having one end pivoted adjacent the first roller extends within the frame under the cam piece connected to the release lever provides a force transfer structure for a strap is inserted between the tongue and the frame bottom surface, around the first roller to pass between the cam piece and the other side of the tongue. Other transverse rollers may be included in the frame to form a pulley arrangement and one end of a frame side wall may be convolved to form a hook assembly.

REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent application Ser. No. 12/802,845 filed on Jun. 15, 2010 which, in turn, obtains the benefit of the earlier filing date of US Provisional Application Ser. No. 61/338,993 filed on Mar. 1, 2010 and the benefit of this earlier filing date is claimed for all matter common therewith.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to motorcycle transport restraints, and more particularly to restraining strap clasping mechanisms combined with pulley pivots for increasing the force levels obtained from the combination.

2. Description of the Prior Art

The outdoor recreation customs and habits that have developed here in the United States adapted to the grandiose and large landscapes of the country, with a consequent reliance on all sorts of motorized vehicles that either bring us closer to nature, as for example the motorcycle, or are specialized for off-road and/or all terrain use. At the same time the grand dimensions of the country and its economic stability have also evolved a well developed highway system which then has even further accommodated this same exact result. Simply, when we sing about ‘spacious skies’ we are stating what's actually there, a common recognition of facts which are also the same facts that drive our outdoor recreation habits.

As result the ubiquitous presence of vehicles carrying other vehicles on our highways is a known fact, as is also the need for the mounting and dismounting assistance and the attention to details of the convenience of any restraint of the carried recreational vehicle. Within this backdrop I have earlier devised several mechanisms that in one way or another assist in the lifting and dismounting a recreational device like a motorcycle or a personal watercraft as exemplified in the teachings of U.S. Pat. Nos. 4,790,713 and 4,932,829 that were issued to me, and in my published US patent application 2005/0111945.

More recently I have described even further improvements in lifting mechanisms such as those disclosed in my co-pending U.S. patent application Ser. Nos. 12/321,267 filed Sep. 2, 2008 for a truck bed carrier and 12/384,630 filed Apr. 8, 2009 dealing with the confined lifting geometries associated with an enclosed carrying vehicle, both of which I now incorporate by reference as if fully set out at length herein. In each of these instances, and also throughout the teachings of the mechanisms developed by others, once the initial positioning of the carried vehicle is achieved it then needs to be restrained for transport by cables or straps that limit the range of movement of the carried vehicle's suspension components.

Simply, it is well appreciated that any extended transport is likely to entail occasional road and/or traffic conditions that result in dynamic loads requiring some restraint on the range of the relative motions of the carried vehicle within its carrying space. Anticipating these potential events a prudent user will typically limit the range of relative movement of the carried vehicle by adjustable cables or straps which compress the vehicle's suspension geometry to limit its remaining stroke which then limits the carried vehicle's response to road shock, thus limiting any induced relative motions to avoid any contact with the carrying vehicle, a matter of particular significance when the transport vehicle space is confined, as in the '630 application above. These restraints often require very large tension levels, particularly when robust suspension elements need to be controlled.

In the past the development of large restraining forces was typically obtained by winding up a flexible strap onto a ratcheted spool or pulley restricted against unwinding by a spring loaded pawl engaging a ratchet wheel, as exemplified in the teachings of U.S. Pat. Nos. 7,416,167 issued to Knox, 6,547,218 issued to Landy, and many others. These mechanisms, in virtually each instance, rely on the radial dimension of a crank handle or lever, or a complex gearing structure, for obtaining the necessarily high restraint forces. Thus while suitable for the purposes intended, the need for a wind-up mechanism and a lever dimension necessary to produce the desired level of force limits the usefulness thereof in the cramped surroundings associated with an articulated lifting assembly.

Simply, the space that is cluttered by the components of an articulated lifting mechanism leaves little accommodation for any fixed wind-up mechanisms, operated by levers and the like, particularly when variously shaped carried vehicles are entailed. For these purposes the conveniences of a flexible strap, or even a rope, are more favorable as the restraint mechanisms both in their aspects of engagement and also in the course of tensioning where techniques of force multiplication, like that obtained from a set of pulleys, may be utilized in combination with clamping buckles in order to form a generally universal tensioning assembly that is useful in the most crowded settings, including those associated with the lifting mechanisms exemplified above.

The clamping buckles that are particularly adapted for these modifications are cam buckles including a one piece frame exemplified by buckles sold under model designations 40880-22; 42195-11; or 40880-15 by Ancra International, LLC, Hawthorne, Calif. Cam buckles of this type typically include a generally C-sectioned unitary frame supporting a pivot extending between the lateral walls thereof on which a spring biased lever is pivoted to press a toothed cam against a strap or belt extending through the frame interior. Once grasped against the strap tension the engagement of the cam is then released only by pressing the lever against its spring bias, thereby lifting the cam from its captured position against the strap.

I have found that in the foregoing cam buckle structure the lateral walls of the single piece frame can be rendered even more useful to serve as supports for additional pivots about which the strap can be looped in order to obtain the load multiples of a pulley. The positioning of these further pivots relative the cam/lever combination compressing the strap can then be further enhanced both to simplify the articulation of the lever for release and to deploy a load bearing pivoted panel between stacked straps under the cam. Moreover, in order to safeguard the larger forces that are thus obtainable from inadvertent release a manually operated eccentric latching pivot may be provided to selectively restrict the motion of the release lever from inadvertent release at these higher load levels now possible. In this manner all the improvements adapting this well known device for increased loadings are conveniently accommodated in a single structure and it is the synergistic combination of all these features that I now describe.

SUMMARY OF THE INVENTION

Accordingly, it is the general purpose and object of the present invention to conform a single piece frame cam buckle assembly for multiple loop load multiplication.

Further objects of the invention are to provide a manually operable safety lock in a single piece frame cam buckle conformed for multiplied loading.

Other and yet additional objects of the invention shall become apparent upon the inspection of the description following in conjunction with the accompanying illustrations.

Briefly, these and other objects are accomplished within the present invention by conforming a single piece frame of a cam buckle to include a plurality of transverse pivot rollers bridging across the lateral walls of the frame distal of the spring loaded pivoted lever carrying the cam that clamps the load carrying strap captured within the frame. A manually articulated eccentrically pivoted interlock is also mounted to bridge across the frame adjacent to the free end of the release lever to select its releasing displacement by the gap in the eccentric projection thereof but to oppose the release of the strap throughout all the its other radial alignments, thus accommodating a single-handed restraining sequence of the carried vehicle. The selective placement of the foregoing pivot rollers relative the cam lever pivot are then useful to multiply the number of loops of the load carrying strap and also to selectively support a pivoted tongue panel extending between the strap layers compressed by the cam to increase the cam forces that capture the free end of the strap.

Alternatively, the pivot axis and radial dimensions of the turning roller which aligns the strap onto the tongue, and also the arcuate form of the tongue, may each be selected so the stretched strap portion extending thereover contacts the underside of the release lever so that the increasing strap tension effects an interlock. In this form the interlock itself may be omitted as the mechanism is thus rendered self effecting. Of course, this last form obtains even further simplifying results as the strap induced forces opposing the release lever effectively also replace the function of the springs.

In either form the single piece frame may be further modified to extend as a longitudinal projection one of its side walls that is then bent into a partial U-shaped hook aligned to form a gap between its free end and the end of the opposite sidewall selectively closed by a latch pivoted from the free end of the hook to engage a post on the sidewall both for added load transfer and to retain any tie-down strapping collected on the hook. A conformingly bent reinforcing piece is then welded, riveted and/or otherwise attached to the hook surface to provide the necessary strengthening that may be result from any force multiplication provisions that are obtainable by looping the primary strap over corresponding pivot rollers mounted in a similarly provisioned complementary assembly.

It will be appreciated that in the normal course only one cam buckle assembly is needed to effectively perform any restraining or release. The complementing second piece that forms the other part of the pulley assembly may therefore be implemented as a single frame piece only, omitting the latching lever to conserve fabrication costs thereby utilizing a single fabrication process for both ends of the pulley assembly thus obtained.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective illustration of a prior art cam buckle assembly deployed for restraining use;

FIG. 2 is yet another perspective illustration of the inventive cam buckle assembly adapted for force multiplying interconnection in accordance with the present invention;

FIG. 3 is a further perspective illustration, separated by parts, of the inventive cam buckle assembly shown in FIG. 2 conformed for a force multiplying interconnection to a pulley arrangement in accordance with the present invention;

FIG. 4 is a sectional view taken along line 4-4 of FIG. 2;

FIG. 5 is yet another perspective illustration depicting a modified arrangement of the assembly shown in FIGS. 2-4 for providing a complementary interconnection therewith;

FIGS. 6 a and 6 b are each a diagrammatic sectional view illustrating various pulley loop arrangement for various levels of force multiplication;

FIG. 7 is a further sectional view of an alternate form of the invention herein; and

FIG. 8 is yet another perspective illustration separated by parts, illustrating the alternative implementation of the present depicted in FIG. 7.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in FIG. 1 a conventional cam buckle assembly generally designated CB comprises a single piece unitary frame UF of a generally C-shaped section defined by a bottom surface BS spanning between two lateral walls WS1 and WS2. A transverse pivot pin PP extends between the walls WS1 and WS2 proximate the one ends thereof to support an L-shaped lever assembly LA at the junction of a lever LE and a generally orthogonal cam piece CP.

A helical bias spring SP on pin PP is compressed between wall WS1 and the lever LE to urge the free end of the cam piece CP in the direction of arrow AA towards an anvil piece AN supported on the bottom surface BS, capturing a load carrying strap ST therebetween as it is passed through an aperture AP in the bottom surface BS against the tension force TF carried by the strap to an end hook HK corresponding to the manually applied tensioning force at the strap's free end FE. A strap loop SL around the other portion of the bottom surface BS bordering the aperture AP is then useful as the other end of this tension force combination.

While there are many commercial forms of the foregoing cam buckle assembly those skilled in the art will be familiar with the examples thereof sold under model designations 40880-15 or 40880-22 by the Ancra International, LLC identified above for use in restraining motorcycles and other recreational vehicles in the course of transport. Those skilled in the art will also appreciate that in each instance the integral, single-piece frame UF and the strap capturing bias of the lever assembly LA results in a reliable restraining capture against all sorts of forces imposed in the course of transport, and it is this load capacity that has driven the commercial success of this elegantly simple device. Limiting this wide utility, however, is the physical constraint of the human anatomy to generate large forces, a constraint inventively resolved by the inventive force multiplying and locking mechanisms described below.

By reference to FIGS. 2-4 these self-effecting high clamping levels obtainable in the foregoing cam buckle assembly can be even further improved by modifying its unitary frame to serve as a part of a secured pulley arrangement, thereby obtaining the higher restraint force levels that are now required in the transport of heavier and more complex motorcycles or recreational vehicles. Like numbered parts operating in a like manner to that previously described, the inventively modified cam buckle assembly generally designated by the numeral 10 once again includes a unitary frame 11 in the form of a C-sectioned channel piece generally like the unitary frame UF in FIG. 1.

In a manner similar to the prior cam buckle structure unitary frame 11 is similarly defined by a lower surface BS bordered on either side by sidewalls WS1 and WS2. A bridging pin PP then extends across the sidewalls WS1 and WS2 to pivotally support the lever assembly LA which may include the biasing springs SP to assist in urging the lever LE around its pivot to press the end of the cam piece CP against strap ST as it is supported on an arcuate support plate 12 pivoted from a mounting pin 12P spanning across frame 11 to pass through a pair of leading edge ears 12E between which a turning roller 14 mounted on the same pin 12P is received so that the concave aft surface 12A below cam piece CP forms an opposing structure on which the strap is compressed.

A further transversely bridging pivotal post 15 is then mounted across frame 11 subjacent the pivotal arc of the free end of the lever LE shaped as a generally cylindrical cam surface 16 that includes a chordwise flat 16F to provide clearance for the pivotal displacement of the lever LE to release the clamping engagement of the strap ST once the flat 16F is aligned below the lever end. A manually operable knob 17 of the exterior end of post 15 is then provided to facilitate the above clearing alignment, thereby allowing the user manual control over the release of the captured strap. Of course, the dimensions of the remaining periphery of cam surface 16 is then useful to keep the cam buckle locked, thereby securing the higher total tension forces that are now obtainable

Those skilled in the art will appreciate that dimensional geometry of the foregoing arrangement can be selected so that as the strap ST is guided along the bottom surface BS and then under the pivoted support plate 12 to turn around its rounded leading edge roller 14 it will then stretch above and across the concave portion of the aft piece 12A to make contact with the surface of cam 16. The force applied to the free end FE of the strap ST is thus also resolved as a friction shear force on the cam and as the manual force MF is increased the turning moment imposed on cam 16 also increases, to a point where the flat 16F is displaced by turning to lock the strap clamping engagement by the cam piece CP.

These increased forces can be obtained by providing a further turning roller 18 supported on a post 18P bridging across frame 11 distal of the lever assembly LA. This additional turning roller can then be used either as the end attachment of the strap end FE or as the mechanism for one more pulley loop as exemplified in the diagrammatic illustrations in FIGS. 6 a and 6 b. Of course, in each instance the parts described above can be selectively combined to form a complementing pulley arrangement illustrated in FIG. 5 around which the strap may be looped.

More precisely, a similarly constructed complementing structure generally referenced by the numeral 50 comprises again a C-sectioned frame 51 across which pivot rollers 58-1 and 58-2 on bridging posts 58-1P and 58-2P are then useful to form the other connection for the pulley loop, both the frames 11 and 51 including bent-over extensions 19 of one of the sidewalls thereof each reinforced by a reinforcement 19R to form a connecting hook for engaging either the carrying or the carried vehicle selectively closed by a pivoted latch 19C engaging a lateral post 19P on the frame exterior.

By reference to FIGS. 7 and 8 a further interlock alternative, generally designated by the numeral 110, may be obtained by selecting a larger turning roller 14-1 so that geometric relationship is developed that stretches the strap underneath the release lever LE whereby as the tension is raised the cam piece CP is driven to capture the strap. Like numbered parts operating in a manner similar to the description previously set out, the strap segment passing from roller 14-1 extends below the end of lever LE on its way over tongue 12A to the engagement by cam piece CP producing a lever displacement that locks the cam and as the strap is drawn taut. Once thus engaged the other portion of strap ST passing between the tongue 12A and the bottom surface BS is also compressed effecting an interlock as long as a load is applied. This particular geometric interlock therefore assures a consistent latched state as long as the tension is maintained, thereby obviating the need for the customary springs SP.

This last feature is particularly useful in a setting, like here, where the springs of an undercarriage of a transported vehicle are compressed by the strap tension itself, thereby assuring a continuous level of tension that insures an interlock. Once delivered to the destination a release is easily achieved by simply loading the transported vehicle to unload this pre-stress at which point the interlocked engagement is relieved, allowing the articulation of the releasing lever LE.

It will be appreciated that the foregoing arrangement provides the added security of a safety interlock within the same mechanism that is used to develop the multiplication to much higher force levels, thus resolving the concerns associated therewith. Moreover, convenient techniques like surface knurling and/or edge rounding can be applied to accommodate the various strap weaves and material selections, thereby reducing inventory and fabrication concerns while also advancing safety. As result, an inexpensive and rugged mechanism is provided that us widely useful in various applications.

Obviously many modifications and variations of the instant invention can be effected without departing from the spirit of the teachings herein. It is therefore intended that the scope of the invention be determined solely by the claims appended hereto. 

1. In a cam buckle assembly characterized by a frame including an elongate bottom surface, a pair of side surfaces along the edges of said bottom surface, a lever assembly defined by a release lever cantilevered at an angle from a cam piece and pivotally mounted in said frame at the common juncture therebetween, the free end of said cam piece extending towards said bottom surface over a portion of the pivotal movement thereof, and a flexible strap aligned for capture between said cam piece and said bottom surface, the improvement comprising: a first turning roller mounted for rotation in said frame proximate the free end of said release lever; a generally elongate tongue pivotally deployed at one end thereof adjacent said first turning roller within said frame convolved along an arc to extend the free end thereof between the free end of said cam piece and said bottom surface, a portion of said strap being received between said bottom surface and said tongue and wound about said first turning roller for insertion of a segment thereof between the free end of said release lever and said tongue for urging said release lever about the pivotal mount thereof.
 2. Apparatus according to claim 1, further comprising: a second turning roller mounted for rotation in said frame proximate said cam piece.
 3. Apparatus according to claim 2, wherein: one end of a side of said frame proximate said first turning roller forms a hook.
 4. Apparatus according to claim 3, further comprising. closing means secured to said hook for selectively closing the opening in said hook.
 5. Apparatus according to claim 1, wherein: one end of a side of said frame proximate said first turning roller forms a hook.
 6. Apparatus according to claim 5, further comprising. closing means secured to said hook for selectively closing the opening in said hook.
 7. In a cam buckle assembly characterized by a frame including a bottom surface, a lever assembly defined by a release lever cantilevered at an angle from a cam piece and pivotally mounted in said frame at the common juncture therebetween, the free end of said cam piece extending towards said bottom surface over a portion of the pivotal movement thereof, spring means for urging said cam piece against said bottom surface, and a flexible strap aligned for capture therebetween, the improvement comprising: a first turning roller mounted for rotation in said frame proximate the free end of said release lever; an elongate tongue pivotally deployed adjacent said first turning roller and extending in an arcuate form within said frame to deploy the free end thereof between the free end of said cam piece and said bottom surface, a portion of said strap being received between said bottom surface and said tongue and wound about said first turning roller for insertion between the free end of said cam piece and said tongue; and a cam interlock mounted for rotation in said frame in an alignment subjacent said release lever including a radially extending enlargement for urging said lever assembly to compress said cam piece against said strap portion on said tongue.
 8. Apparatus according to claim 7, further comprising: a second turning roller mounted for rotation in said frame proximate said cam piece.
 9. Apparatus according to claim 8, wherein: one end of a side of said frame proximate said first turning roller includes a hook.
 10. Apparatus according to claim 9, further comprising. closing means secured to said hook for selectively closing the opening in said hook.
 11. Apparatus according to claim 7, further comprising: one end of a side of said frame proximate said first turning roller is convolved to form a hook.
 12. Apparatus according to claim 11, further comprising. closing means secured to said hook for selectively closing the opening in said hook.
 13. In a cam buckle assembly characterized by a frame including a bottom surface, a lever assembly defined by a release lever cantilevered at an angle from a cam piece and pivotally mounted in said frame at the common juncture therebetween, the free end of said cam piece extending towards said bottom surface over a portion of the pivotal movement thereof, and a flexible strap aligned for capture between said cam piece and said bottom surface, the improvement comprising: a first turning roller mounted for rotation in said frame proximate the free end of said release lever; a generally planar tongue pivotally deployed in said frame to extending the free end thereof between the free end of said cam piece and said bottom surface, a portion of said strap being received between said bottom surface and said tongue and wound about said first turning roller for insertion between the free end of said cam piece and said tongue;
 14. Apparatus according to claim 13, further comprising: a second turning roller mounted for rotation in said frame proximate said cam piece.
 15. Apparatus according to claim 14, wherein: one end of a side of said frame proximate said first turning roller forms a hook.
 16. Apparatus according to claim 15, further comprising. closing means secured to said frame for selectively closing the opening in said hook.
 17. Apparatus according to claim 13, further comprising: one end of a side of said frame proximate said first turning roller is convolved to form a hook.
 18. Apparatus according to claim 17, further comprising. closing means secured to said frame for selectively closing the opening in said hook. 